Phytochemical study on Melilotus officinalis leaves: Green synthesis of silver nanoparticles and quantitative analysis of phenolic compounds

Since ancient times, people have used plants as food and medicine. Bioactive chemicals in plants have been identified and used in medicinal development since the discovery of spectroscopy. Nanotechnology is a branch of science that has developed rapidly in recent years due to its widespread application. In this study, silver nanoparticles (AgNPs@Mo) were synthesized by a green approach using the Melilotus officinalis leaves. The structure of the nanoparticle was identified by analytical techniques. The maximum absorption at 483 nm confirmed the formation of silver nanoparticles. The TEM image presented the morphology and particle size of nanoparticles (36.3 nm). The XRD spectrum determined the shape of nanoparticles as a face-centered cubic structure (fcc). The particle size was also determined by the Scherrer equation as 32.4 nm. The zeta potential (-31.1 mV) revealed the high stability of nanoparticles. Quantitative analysis of phenolic compounds in M. officinalis leaves was determined by LC-MS/MS, and coumarin (2.167 µg/g extract), syringic acid (0.027), salicylic acid (0.025), and rutin (0.066) were defined as major compounds. Melilotus officinalis leaves may be a valuable source for silver nanoparticle synthesis.